Over the weekend, Canada held its first national blind hockey tournament. How do visually impaired people play hockey? With a big, hollow puck 10 centimeters across and filled with metal nuts and bolts that rattle. Players follow the sound around the ice:

“Blind hockey” is a bit of a misnomer, since the sport is played by both fully blind players and those who have as much as 10 per cent of their vision. Those with the most vision tend to play forward as they are best suited to making shots on goal and passing. Lower-vision players tend to play defence, while players with the least vision or no vision play goal, since they don’t need to move around the ice as much.